It would be fair to say that Randy Vandagriff knows inkjet. He has been involved in the technology for at least 40 years and has been the driving force behind the Prosper Ultra 520 press that Kodak is backing as the future direction of its business. Vandagriff’s presence on Kodak’s board and the presence of executive chairman and CEO Jim Continenza at Hunkeler Innovation Days, serve to confirm just how important this machine will be.
The Nexpress and Nexfinity line of toner presses has been parked. There are questions over the very long term viability of aluminium printing plates if only because the energy required to produce the aluminium, shape it into a printing plate and to ship it around the world. Continenza has been open about the environmental impact that this has and believes it will eventually prove unsustainable. Inkjet though is another matter. The inks are water based and only those that reach the paper are used, the remainder is recirculated. Kodak’s inkjet technology is continuous, where droplets that are not being used to form the image are defected from their flightpath, making this technology more land on demand than drop on demand.
The Ultra 520 is the ultimate expression of this technology to date at least. It represents 40 years of development from the technology housed inside vast cabinets to printing addresses for magazine publishers at 200dpi to a technology that is capable of matching litho print quality. It has grafted to that core technology all the print knowledge that Kodak has through plates, workflow and colour management.
Kodak, perhaps uniquely, does not talk about the resolution of the press in nozzles per inch, but states that resolution is 200 lines per inch, a reference that litho printers will be familiar with.
For reference, the print resolution is 1800x900dpi with 3.5pl droplets and a colour gamut that comfortably exceeds Fogra 51.
The other frame of reference is productivity, how much work the press can get through in one hour, or more importantly how much work can a business reliably expect to get from the press in that hour. “The important factor is not so much the cost per page but how many production hours you can get out of a machine,” says Continenza. By that measure the Prosper 7000, positioned for book and newspaper printing, hits the mark being twice as productive as the Prosper 5000 and able to print at 410m/min for these application where the focus is on productivity rather than the finest quality.
The machine that does this is the Ultra 520 and Kodak firmly believes will drive the litho to inkjet transition that has been promised since the first Prosper appeared in 2008. That superseded the Versamark era printheads which had established inkjet as a technology for high speed variable data, but alongside litho printing rather than supplanting it. The Ultra 520 is intended to administer the death knell to that approach. This is the press that can replace litho printing.
It appeared for the first time in Europe at the Hunkeler Innovation Days and that press has stayed in Europe. The haggling over where it will be placed had not yet resulted in announcements about the pilot customer on this side of the Atlantic. At the same time, the first US customer has been agreed “with a handshake” says Vandagriff.
This is a customer that currently has two toner based digital presses and B1 litho presses. Both toner machines and one litho press will be replaced by inkjet. That will provide the the inkjet press with the volume to underwrite the investment with more to come as more litho migrates to inkjet over time, says Vandagriff.
The Ultra 520 is big. It is taller than the Prosper 6000 that has been Kodak’s flagship until now and development has leveraged its experience of that press. As one example, the head cleaning process is far simpler. An operator has no need to poke underneath the press to reach the heads for cleaning, the print array now slides out and can be reached standing up. The cleaning cycle has also been extended.
The Ultra is built to last, as well as to be practical to operate. Kodak does not need users to be pioneers, but to be hard headed business led printers that can calculate costs and understand where their business is headed. Productivity on any paper is essential to this equation. Throughput is 150m/min with one level of quality. A pre coating would be advised to optimise the surface for the water based inks, providing extra lift, but is not essential.
“At Hunkeler were we were surprising customers and competitors because they are not able to run at that speed and at that quality. Customers thought the quality is great,” says Vandagriff.
Progress with initial customers will be crucial. It would be straightforward for Kodak to band sales projects and forecasts of the number of installs it might have by Drupa say, but this is a long term play. The experience from the early adopters is more important than the number of machines in the field – at least at this point in the story.
This is a switch in policy from the early days of the printhead. It made its debut at Drupa in 2016 on a roll to roll test rig to provide some idea of quality OEM developers could expect. The plan was then to sell the Ultrastream heads to other manufacturers to implement in their machines. Kodak would not be building the presses.
That has changed. Kodak will still provide heads to markets that it is not engaged in, so there are deals for the personal hygiene products market (think nappies and similar products) and for flexible packaging with Uteco. Others will follow in more arcane applications. But for commercial printing, the Ultra 520 is the vehicle to get the printheads and the ink into the market. Each press is capable of consuming more 15,000 litres of ink (4ml per page). Kodak needs customers handling this sort of volume.
“We are looking at prospects that are doing some digital printing, but with offset and can consolidate their litho machines with digital,” says Vandagriff. “The result will be a mix.”
Existing Prospers have enabled litho printed newspapers, books, transactional documents and more to migrate to digital printing, where quality demands were not necessarily of the highest level. “This machine will see a move from high quality toner machines,” he says. “There has been interest interest from high coverage direct mail printing on both coated and uncoated papers and a number of customers we have spoken to are producing photobooks while there is also a lot of pressure to push towards book of one production.”
Because this is a continuous inkjet technology where the ink is flowing constantly through the nozzles, there is less risk they will clog up because of dried on ink. This means too that the ink recipe does not need as much glycol or other additive to prevent drying around the orifice.
The unwanted side effect of inks with high levels of humectant is that it is difficult to dry on the paper, driving up the energy load and the sustainability issue which is a concern for all those that talk to Kodak, says Vandagriff.
The press uses NIR dryers which are tuned to evaporate the water in the ink and minimise the heating effect on paper. This helps reduce stress and thus distortion of the paper and can be tuned to the ink coverage on that job. Despite suggestions that NIR does not work well across all colours, Vandagriff states that “we do not have trouble with drying. And because our inks do not have the humectant levels that others need, drying is actually much easier for us”.
That will be important for flexible packaging where thin plastic films do not take kindly to extraneous heat, nor offer the absorbency of paper. Different ink sets will be needed for different applications.
The DFE is also Kodak’s own design based around experience with Prinergy and Creo DFEs and using Adobe’s APPE 5 Rip. It does not quite Rip on the fly, but Kodak is confident that in practice it will not have to.
Under Continenza, Kodak is far more cautious about where it spends its money. It took the risk of coming to Hunkeler Innovation Days. From the expressions of all on the stand, from the CEO down, it has been worth it.
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